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Cold air Intake? - Not a Joke or Noob question

Discussion in 'Gen 2 Prius Accessories & Modifications' started by Daves09prius, Feb 11, 2012.

  1. 69shovlhed

    69shovlhed Surly tree hugger

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    hey! relax, dave. at least don't tell them to drive their prius off a cliff. get em to borrow an suv from a small d!¢ҝəđ friend first. (all those suv drivers got small d__ks)
     
  2. Daves09prius

    Daves09prius Active Member

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    I agree with you 100% more power requires more fuel.
    The baffle I'm talking about is this (item #13): [​IMG] [​IMG] [​IMG] [​IMG]
    The last picture is the bottom of the baffle. Those 4 tiny holes is what the air is being sucked through, essentially choking the engine of air and power.

    With the baffle removed the MAF senses that there is more air being pulled in, the computer adds additional fuel to compensate for the added volume of air.

    More air + More fuel = Increased acceleration
    Increased acceleration + P&G = shorter pulse
    Shorter pulse + Longer glide = Improved MPG

    Am I wrong? probably. but that's my explanation.
     
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  3. Daves09prius

    Daves09prius Active Member

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    I don't WOT for my pulse. I barely have to touch the pedal to get a strong pulse. I agree a WOT pulse would result in wasted energy and additional fuel usage. I think my ability to maintain forward motion, and avoid unnecessary braking helps. I also think the route I drive to and from work help. On the way to work it is highway, almost all down hill, so I can coast a lot. On my way home I take back roads that have gradual hills, so I can coast on the decents. If I drive the highway home it's all uphill coupled with heavy traffic moving at 75/80 speeds yeah, no fuel efficiency there.

    I tried to P&G on my wife's corolla, and couldn't get any better mileage out of it. Of course with the corolla the ICE is always running even when coasting, but since the engine isn't under load it should still make a difference in MPG...
     
  4. richard schumacher

    richard schumacher shortbus driver

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    There's no delusion like self delusion :_> Show us the dynamometer and tailpipe emissions data.
     
  5. 69shovlhed

    69shovlhed Surly tree hugger

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    actually, those 4 holes are water drains. the air inlet is in the engine compartment where part #11 attaches to #8. so it is sucking in hot air from just under the rf corner of the hood. #11 looks to me to be restrictive; pulling off #13 should allow more cooler air in, but heaven forbid you run through a deep puddle at speed. the filter probably doesn't like being wet, even if water doesn't get into the maf.
     
  6. xs650

    xs650 Senior Member

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    Your "baffle", item 13 is called a resonator, more precisely a Helmholtz Resonator. They are normally plumbed into the side of an air intake system to tune out noise or sometimes to smooth out air flow at certain engine speeds. They don't restrict airflow because they aren't normally in the flow path. They may actually improve airflow over a narrow engine speed range by smoothing out the airflow.

    Those small hole in the bottom are probably just moisture drain holes.
     
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  7. edthefox5

    edthefox5 Senior Member

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    Dude I understand your excitement but really there's nothing there except a louder intake. Most cars have intake resonators. It makes them quieter and helps remove intake turbulence if you come off the pedal real fast or wot
    like 650 says.

    And as far as getting to P & G quicker what does that matter? You will have the same distance P & G'ing before you have to apply gas again no matter how fast you get to it. Just because I get up to speed faster to P & G that doesn't make the glide goes further.
    And you stating that you approach the speed/spot to P & G faster means to me you must have more HP & torque. Noticeably more. Which is impossible. That would mean at least 10 more horsepower to notice it.
    That's alot of horsepower. Do you know how much money you have to spend to get 10 extra horsepower out of a modern car?Its like trying to make our cars handle better. Expensive.
    But anyway keep trying. Its fun to try stuff on our cars.
     
  8. qbee42

    qbee42 My other car is a boat

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    Since you aren't getting close to WOT, the ICE is not starved for air. Any gains you make reducing intake restrictions are compensated for by the partially closed throttle plate. This is just simple physics. Removing intake restrictions is only meaningful at or near WOT.

    As for the Corolla, a real hypermiler like Wayne Gerdes can do wonders with P&G with any car. He got 59 mpg in a plain old Accord.

    Tom
     
  9. xs650

    xs650 Senior Member

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    I spent a couple of years as a test engineer, including vehicle performance testing. I've also modified air intake systems. Despite having made accurate performance measurements that showed no improvement in performance, my seat of the pants impression was that the mods made the car accelerate better. I can really understand how someone with no instrumented performance background can get fooled into thinking they are getting more performance when they aren't.
     
  10. joedirte

    joedirte Member

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    Not only that, isn't the response time of the A/F sensor pretty fast and will adjust the mix along with the MAF sensor?! At the very least if this mod did work, your fuel trims should maybe read differently, is that still the same?
     
  11. qbee42

    qbee42 My other car is a boat

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    Never underestimate the power of the placebo effect. My car is noticeably smoother and drives better after I wash it.

    Tom
     
  12. Daves09prius

    Daves09prius Active Member

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    Now I'm glad we're all discussing this and not attacking each other. I didn't know the tiny holes at the bottom of the resonator were for water. So then the only place the intake is pulling air from is the snorkel in the engine compartment - Which makes sense because the air-flow would follow the path of least resistance. So the engine is sucking in warm/hot air from the engine. So why not just attach a small filter onto the side of the air-box for improved air flow, but still maintaining warm/hot air intake? would that conceivably improve acceleration?

    More on the Atkinson Cycle:

    Animated Engines - Atkinson

    This video is just for fun:


    I still believe removing the resonator improves acceleration due to increased air flow. I'm happy to agree to disagree. Try it and see for yourself. Things may not work on paper, but when tried in practice, they somehow miraculously work.

    Thanks for everyone's input.
     
  13. Justdidit

    Justdidit LVNPZEV

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    Do you have any pictures of this or could u snap one? I'd like to know more about this also...
     
  14. xs650

    xs650 Senior Member

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    The throttle body heat is there to prevent throttle body icing in cold weather, not vapor lock. It also helps a bit with fuel atomization because of the warmer intake air. Fortunately, neither of those matters much when it's warm-hot out.
     
  15. tf4624

    tf4624 Active Member

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    Lol I took this junk out long ago.
     
  16. Daves09prius

    Daves09prius Active Member

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    TF4624 - what difference, if any did removing the resonator do for you? Doesn't have to better mileage. Did you notice More acceleration? Or more torque etc... Or no difference at all? Because that's what's in question. Will removing the resonator what I refer to as a baffle. I call it a baffle because it's easier to type, and i dont have to fight with spellcheck on my iPhone. Will removing the resonator result in any positive change in mileage, power, throttle response etc. in the Prius ?

    P.S. So your Prius didn't blow-up after you removed the resonator, right?
     
  17. Justdidit

    Justdidit LVNPZEV

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    No, to answer your question..it won't... at least it hasn't blown up mine....YET. :)

    I wanted to see how hard/easy it was to pull my headlights last night because i plan on baking/blacking them out soon. Seriously, no kidding, I had both OEM HID headlight assembles out in 5-7 min. HA! it was great. While i had the passenger side out, i did remove the baffle/resonator..whatever you want to call it. Since it is so easy to remove, I will put it back in for testing once i purchase the Kiwi Bluetooth OBDII adapter and can log some diagnostics. From the first drive, I can already tell you it feels just Dave09Prius said, the car doesn't have to work so hard to accelerate at any speed. Can't prove that there was a hp increase or mpg decrease until I can log the results. There isn't a noticeable difference in engine noise either. Haven't noticed a drop or increase in MPG either, but i've only driven to work since the removal. So far...so good, i like the 'feeling' that it is accelerating faster/easier.
     
  18. qbee42

    qbee42 My other car is a boat

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    By accelerating faster, do you mean that it has more acceleration at full throttle, or that it takes less throttle for a given amount of acceleration?

    For a normally aspirated engine like that in the Prius, the only way to control power output is restrict the air intake. Regardless of what sort of air intake system you use, for a given power output less than WOT, something is restricting the air intake. Normally this is the throttle plate.

    Reducing air flow restrictions upstream only means that you will use a more restricted throttle plate setting for a given amount of power. It won't increase efficiency.

    WOT, on the other hand, is a different issue. At WOT the throttle plate is full open. Reducing upstream restrictions will allow for more power, assuming the engine is capable of using the additional airflow.

    Tom
     
  19. Justdidit

    Justdidit LVNPZEV

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    Currently I know that i don't have to press the gas pedal down as much to get the car to accelerate as quick as before with WOT. Or so it 'feels' :) like the freshly clean car going feelin faster than the dirty one. lol - Still need to log some results before this is more clear. Or if anyone wants to try, removing the restriction from any Gen2 takes less than 15 from start to finish -all done with a 10mm socket and a philips screwdriver.
     
  20. tf4624

    tf4624 Active Member

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    The prius didnt blow up.. sorry doesnt do that.. I have other mods that could make it blow up LOL


    i say yes there is a difference, that being positive .. but there is another piece 2 pieces you need to remove.. 1 get rid of completely .. even if its against the Toyota book.. and 2. replace something.

    i see and feel more acceleration with Wide Open Throttle *WOT..... but thats me.. I drive my price like its a race car.. that i mean with cornering .. cant do much on a straight away..

    i also modified the Throttle it self for more power without sacrificing the MPG.. i made it gain more without trying.. yea i can have green on my Battery meter when driving.. most of you unless your a plug in .. rarely see the "Green" bars when driving on your Battery meter LOL

    One last thing, ive modded my throttle plate also.